Alex Ferguson praised his latest captain fantastic as Wayne Rooney inspired Manchester United to the brink of qualification for the Champions League knockout phase.

Rooney was handed the captain's armband 15 minutes before kick-off after late withdrawals by Ryan Giggs and Rio Ferdinand left United short of experience and the 20-year-old responded with a tremendous performance as FC Copenhagen were blitzed 3-0.

Paul Scholes, John O'Shea and Kieran Richardson were the scorers but Rooney was at the heart of United's best moves, and Ferguson believes his young talisman is back to his best.

Ferguson said: "He's quite possibly the youngest player to captain United.

"I was looking around the dressing room only 15 minutes from kick-off and Edwin van der Sar was out on the pitch so I overlooked him - though perhaps with his experience and personality I should have used him.

"You look for someone who could respond to it - Paul Scholes for example doesn't want to be captain again - so it was an easy choice giving it to someone that it would give a lift to. He did fantastic and his form is back, as we expected.

"He had joked about it last season - he said within earshot of Roy Keane that he should be captain and that Keane was finished - Roy didn't exactly enjoy that but it was just a wind-up."

Rooney created two outstanding chances for Louis Saha and another for Ole Gunnar Solskjaer, as well as coming close to scoring himself, but it took a trademark drive from 31-year-old Scholes to break the deadlock.

A lucky deflection off O'Shea's standing leg for the second ended the contest against the Danes before Kieran Richardson, aided by a slip from Copenhagen keeper Jesper Christiansen, wrapped up proceedings.

After three successive wins in this competition, a single point from their three remaining matches would see United go through - in stark contrast to last season's campaign when they struggled to score and eventually failed to reach the last 16.

Ferguson added: "The only concern I had tonight was that with the chances we created in the first half we didn't kill them off.

"I thought technically they were very good it could had been a doddle if we had taken all our chances. We didn't underestimate them though and I think our players have proved themselves.

"They have grown up. They don't want any more embarrassments and they played well into the bargain.

"We know exactly all about last year and we are not getting a repeat and that speaks highly for the team and their motivation - and more importantly the expression of their football was really good."

Ferdinand cricked his neck in the warm-up and his condition will be monitored in the build-up to Sunday's Premiership match against Liverpool. Giggs and Gary Neville should both be available after missing out against the Danes and Gabriel Heinze could also be in contention.

FC Copenhagen coach Stale Solbakken admitted United had outclassed his side.

Solbakken said: "We lost to a better team but it gave me great hope for the future because we played very well in the first half and created chances all the way through that period.

"It shows that we need only a little bit more experience, two or three players, to compete at this level.

"I actually do think we can beat them at home - we have to play even better but if Sir Alex Ferguson rests a couple of his best players because they are through we could win or at least take a point."